The present invention relates to readily absorbable pharmaceutical formulations of pharmacologically active agents, in particular bases, which are poorly absorbable per se, and to a method for preparing such formulations.
It is well known in the art that in order to obtain a similar pharmacological effect, a number of pharmacologically active agents require considerably higher dosages if administered in oral, rectal, or percutaneous dosage form than if administered parenterally by means of injection. This is an indication that such pharmacologically active agents are absorbed only to a low extent from these formulations.
Yet, there is a need for pharmaceutical formulations which provide such per se poorly absorbable pharmacologically active agents not only in an injectable formulation, but also in orally and/or rectally and/or percutaneously applyable formulations which provide a high degree of enteral absorption of these pharmacologically active agents.
Various methods for improving the absorbability of such insufficiently absorbable pharmacologically active ingredients are known in the art. In some cases the absorbability can be improved by means of a technological treatment of the pharmacologically active agent, e.g., by means of micronization, complex-formation, or addition of solubility improving additives. Yet, these techniques exhibit a number of disadvantages.
Special apparatuses or additional process steps during the preparation and/or formulation process are required for some of these methods; or only a limited number and amount of additives can be applied in certain cases due to safety and/or compatability problems. Furthermore, these techniques can successfully be applied only to a limited number of groups of pharmacologically active agents.
Recently, glycerides of fatty acids of medium chain length, containing from about 6 to about 12 carbon atoms, have been used as carrier materials for pharmacologically active ingredients. Yet only a very limited group of pharmacologically active agents can be satisfactorily formulated using triglycerides a a carrier material, due to a poor solubility of most pharmacologically active ingredients in such a carrier material. In particular, various difficulties are encountered, if pharmacologically active bases are to be formulated with glycerides, since these compounds are not sufficiently stable in free base form, and in salt form are not sufficiently soluble.